1. Technical Field
The present invention relates to image processing apparatuses, image forming apparatuses, and recording media.
2. Related Art
So-called overprint processing techniques are known in which a separate image (object) such as characters or diagrams or the like are formed overlapping on top of an image expressing scenery or the like as a background. When overprint processing is carried out, even in a case where the positions for forming the images of multiple colors are displaced from their targeted positions, an appearance of an image defect known as “white gaps” can be inhibited in which the surface of the paper is exposed. Overprint processing in which a separate black image is formed overlapping an image that is set as the background is referred to as black overprint processing.
As one format for describing data pertaining to an image on a computer there is a format in which a process for drawing an image is described using numerical values or numerical expressions and is commonly referred to as a “vector format”. An image forming apparatus such as a printer that receives this data executes a rendering process by interpreting the data, and generates raster format image information in which color information is described that expresses the color of each of the multiple pixels. If this rendering process is executed using a color space defined by cyan (C), magenta (M), yellow (y), and black (K) for example (hereinafter referred to as a “CMYK color space”), which are the colors of colorants used by the image forming apparatus, then black overprint processing is executed by merely specifying the amounts of colorants to be disposed in respective positions on the sheet of paper. For example, this applies to a case where the rendering process is carried out using PS (PostScript). In contrast to this, in a case where the rendering process is carried out using PCL (Printer Command Language) or the like, a color space is used that is defined by red (R), green (G), and blue (B) (hereinafter referred to as an “RGB color space”), which is suitable for displaying on a display, and this is different from the color space defined by the colors of the colorants.